4 Things to Know About the Paris Climate Agreement

December 2015 will go down in history as one of the most important beginnings in history. This was when 196 nations came together to alter the course of our energy future. To channel the vernacular of U.S. Vice President Joe Biden, this was a big F***n deal.

It won't save the planet. At least not in the short term.

But then, no one expected it to. The agreement is historic, but it's just the first - albeit rather large - step toward more sustainable energy systems. Not only do the countries each need to live up to their commitments, but even more steps need to be taken to reduce and eventually eliminate carbon emissions that are causing the warming of our climate.

Here are 4 things you need to know about the agreement:

1) It went even further than expected: There was a lot of confidence going into the meetings that they would result in a substantive agreement. This confidence was based both on American leadership to bring parties to the table and the overwhelming scientific consensus that action was necessary and long overdue. Expectations were that the resulting agreement would set a goal of keeping temperature rise to no more than 2 degrees Celsius over preindustrial levels through the end of this century. The final agreement went even further, stating that we should "pursue efforts to limit the temperature increase to 1.5 degrees Celsius." This more stringent standard is good news for small island nations that are already facing the prospects of disappearing due to sea level rise and other factors. It also reflects the growing scientific belief that a 2 degree rise is way too dangerous. Of course, meeting that level is probably impossible for a lot of reasons, but setting the goal will increase the urgency of taking substantive action sooner, rather than minor action later.

2) It gets started quickly (in a relative sense): While the agreement officially doesn't go into effect until 2020 (which, after all, is only 4 years away), it stipulates an interim review of progress as early as 2018 and further reviews every five years thereafter. This ensures that countries will immediately engage in actions designed to reduce their carbon emissions. Of course, many nations, including the U.S., China, those in Europe, and elsewhere, have already taken steps to reduce carbon and expand renewable energy development. For some (e.g., the U.S.), meeting our early goals will be easy, while others (e.g., China) will have much greater challenges to keep the pace.

3) This is the end of fossil fuels (well, sort of): The agreement makes it clear that fossil fuels are on their way out, even so far as to set a goal for a "global peaking of greenhouse gas emissions as soon as possible." In truth, this was happening anyway because of market factors, but the agreement commits countries to expanding renewable resources like wind, solar, hydroelectric, and others. Does it mean fossil fuels will disappear overnight, or even ever? Of course not. Not only will we still be using gasoline and diesel for fuel and heating for some time, but we rely on plastics for so many products. Plastics are mostly petrochemical based, so clearly there is need for expanded innovation. We also need to shift jobs from coal and oil to solar and wind; that must happen transitionally as workers are trained, new innovative companies are set up, and current fossil fuel companies shift to broader energy investments. But coal in particular will continue to be a bad investment, something that has been true for a long time.

4) Not everyone is happy: As with any negotiated agreement between such disparate interests, no one got everything they wanted. Fossil fuel companies (e.g., ExxonMobil) and oil-based nations (e.g., Saudi Arabia) are obvious candidates for the "we're being treated unfairly" complaints, but then they have enjoyed massive profits for decades while foisting the environmental, health, economic, and national security costs onto the public. At the other end of the spectrum are environmental and health advocates who believe the agreement doesn't go far enough. Included in this category is James Hansen, former Director of NASA's Goddard Institute, author of hundreds of scientific papers on climate change, and now outspoken advocate for action. Hansen thinks the agreement is [expletive deleted], largely because he thinks nuclear energy (which is cleaner, though has obvious issues with radioactive waste disposal and the occasional meltdown potential) should play a larger role.

Still, the agreement sets the world on a path toward sustainability. It's a first step - some may argue it's a very tiny baby step - but it's a step in the right direction. There is much more to do over and above making sure countries follow through on commitments, not the least of which is the potential problem of one political party in the United States denying the science that all the world accepts. But as one advocacy group extols, this is a turning point.